Portable battery-powered communication devices are advantageous in many environments, but particularly in public safety environments such as fire rescue, first responder, and mission critical environments, where voice command operations may take place under noisy conditions. The digital radio space is particularly important for growing public safety markets such as Digital Mobile Radio (DMR), APCO25, and police digital trunking (PDT), to name a few. Accurate speech recognition of verbal commands spoken into radios and/or accessories can be critical to overall communication.
Existing voice detection approaches may suffer from false triggering, a condition in which noise is detected as speech or vice versa. A major challenge for automatic speech recognition (ASR) relates to significant performance reduction in noisy conditions, as current techniques tend to be less robust when operating in very low signal to noise (SNR) environments.
Accordingly, there is a need for an improved method and apparatus for voice activity detection. Portable communication devices, such as handheld radios and associated accessories, such as VOX enabled devices, as well as vehicular communication devices would benefit greatly from improved voice activity detection for voice command operations. It would be a further benefit if the improved voice activity detection could be applied to operations such as noise suppression, echo cancellation, automatic gain control, and other voice processing operations.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.